Catalytic Converters first came to light in Europe. So, with the start of the new emission laws. These laws were introduced to control greenhouse gases emitted into the atmosphere.
"The next thing to affect exhausts was the Vehicle Emissions controls.These were, introduced by the British Government. This required that cars had to be fitted with “Catalytic Converters.” Hence, these cats as we know them, are fitted between the cars engine onto the exhaust pipe system. Gas from the engine is filtered through the cat.Naturally, into a very fine filter system made from ceramics.So, to withstand the high temperature. The cat has also some precious metals.As expected, to help filter out the particulates. (this is why the cats are so expensive)".